Fuse



T. F. COTE June 2, 1931.

v FUSE Filed Nov.

. hollow Patented June 1931 .THOKAS I. COTE, OI CLINTON,

IOWA} ABSIGNOB '10 COTE QROTHEBS FUSE mumorumna coaromnon, or cmmomzowa. a conrona'rron'or nnnawm I was Application filed Iovember 18, 1988. lei-hi No. 318,882.

This invention relates to fuse plugs in general and more articularly to the type of plugs illustrated and described in connection with my rior U. S. Patent No. 1,520,561 of December 23, 1924.

. Plugs of the above ty e have been in use heretofore but have not been so constructed that the fusible element within the fuse cartridge the latter being itself situated within the plug, could be inspected from the outside of the plug so as to determine conclusively whether or not said element had been burnedout.

The primary object of'this invention is accordingly to provide an arrangement whereby it is possible to inspect the fusible element within the cartridge which is itself within the plug, from outside the plug thereby rendering it unnecessary to remove the plu or cartridge to determine whether or not t efuse element has. been burned out.

Other and further objects of this invention will be apparent as the same becomes better understood from an examination of the specification and claims in' connection with the accompanying drawings, wherein:

Fig. 1 is a longitudinal sectional view of a fuse plug embodying this invention.

Fig. 2 is an end view of the cartridge removed from the lug.

Fig. 3 is an on view of the cartridge with the cap thereof removed.

Fig. 4: is a detailed view of the fusible element before the same is installed in the cartridge.

Referring to the drawings more particularly, numeral 1 indicates a body, portion for the plug constructed of any suitable non-conducting material such as hard rubber 'or porcelain. The body portion- 1 is to provide a chamber 2 for' the cartridge and is provided with a closed end 3 having a contact 4 extending therethrough for connecting the cartridge with the center terminal of a socket (not shown). The other end of the body portion 1 is formed open and is closed by a removable cover or body portion 5 of material similar to that of the ortion 1. The cover or body portion 5 as seated therein a ferrule 6 the 18 extends on over sleeve is of reduced width side walls of which have pressed therein screw threads 7' adapted to cooperate with screw threads-8 formed within the portion 5 and also adapted to cooperate with screw threads 9 formed on the portion 1 to detachably secure the two bod portions tother. The screw thread I wall of the errule 6 extends out of the portion 5 and overlies a considerable part of the portion 1 and is adapted to have threaded connection with the usual socket not ShOWIIIf. The portion 5 is provided wit a centra y arranged opening 11 in its top wall in ali nment with an opening 12 in the ferrule and the chamber 2. The opening 11 serves both as a vent and is flared at its outer end as at 13 to facilitate inspection of the interior of the body through said opening.

Thefuse cartridge which is removably situated within the chamber 2 of the plug body is in the form of a sleeve 14.- of insulation material, provided with a suitable vent opening intermediate its ends, spaced from the wall of the chamber and has its ends closed by metal caps 15 and 16 respectively of cup shape. The caps have frictional contact with the sleeve and are adapted to secure the ends of a fuse 17 against the ends of the sleeve. The ends of the fuse 17 are bent angularly and overlie the ends of the sleeve and are retained in engagement therewith by the caps, the major portion of the fuse extending diagonally through the sleeve. One end of the fuse instead of being directly bent over the adjacent edge of the sleeve to overlie the same is first bent so as to extend diametrically across the respective end of the fuse onthe exterior of a disk 18 preferably of fibre which is frictionally engaged in the-corresponding end of the sleeve. The end of the fuse which passes diametrically across the correspondmg end of the sleeve exteriorly of the disk the outer edge of the sleeve and is bent in frictional engagement 'with the cap 16. The dportion of the fuse which is thus presente at the end of the as at 19 whereby the fuse is. bound to blow out somewhere along this portion. In order that this end When the fuse plug is situated in the.

usual fuse socket (not shown) a circuit will be established between the ferrule, the cap 16 which is in engagement with the ferrule at the marginal edges of the opening 12, the fuse 17, the cap 15 and the contact 4 adapted to be engaged by the latter cap.

In practice the portion 19 of the fuse elemerit is painted a distinctive color, for instance red as shown, to render such portion more easily discernible from outside of the plug. Thus one may very readily determine whether or not the fuse is burned out because it is bound to burn out in the painted portion 19 as the same is of reduced width.

The advantages and operation of the aforedescribed plug with its removable cartridge provided with the fuse element which may be inspected from without the plug will be apparent without further description.

I am aware that many changes may be made without departing from the principles of this invention and I therefore do not wish to be limited to the details shown or described.

I claim: i

1. A fuse plug comprising a body provided with anopening and a chamber in communication therewith, spaced contacts at each end of said chamber adapted for con; nection with corresponding terminals in an electrical circuit, a cartridge in said chamber comprising a hollow member, terminals on opposite-ends of said member in electrical contact with said contacts, and a fuse in said member connecting said terminals and havinga narrow portion extending diametrically across the outer end of said member,

' the cartridge being constructed to render said portion visible but sealed from and adjacent to said opening.

2. A fuse plug comprising a body provided with an opening and a chamber in communication with sa1d opening, a pair of spaced contact elements in communication with the interior of said chamber adapted to electrically connect with corresponding terminals in a circuit when the plug is in operative position therein and a cartridge in said chamber comprising a hollow member, terminals on said member in electrical contact with said elements, and a fuse elementin said member electrically connecting said terminals, a narrow portion of said fuse element being disposed diametrically across the outer end of said member in roximity to said opening and the remain er of the fuse element being of substantially greater width, said member being constructed so as to render said portion visible through said opening, the said portion being of a distinctive color.

3. In a fuse plug, a body having an opening at its outer end and a chamber communicating with the opening, circuit contact elements extending into opposite ends of said chamber, a cartridge adapted'for mounting in said chamber having metal caps at each end thereof contacting said contact elements and separatedby a cylindrical hollow non-conductor, the cap at the outer end having an aperture registering with said opening and closed by a mica pane, am

of the outer cap and extending therefrom diametrically across the outer end of the cartridge adjacent said mica pane and thence longitudinally of the cartridge into contact with the other cap, the portion of the fuse adjacent said mica pane being substantially narrower than the remainder of the fuse to assure blowing of the fuse in that portion.

4. In a fuse plug, a body having an opening at its outer end and a chamber communicating with the opening, circuit contact elements extending into opposite ends of said chamber, a cartridge adapted for mounting in said chamber having metal caps ateach end thereof contacting said contact elements and separated by a cylindricaLhollow non-conductor, the cap at the outer end having an aperture registering with said opening and closed by a mica pane, and a fuse link contacting with one portion only of the outer cap and extendingtherefrom diametrically across the outer end of the cartridge adjacent said mica pane and thence longitudinally of the cartridge into contact with the other cap, the portion of. the fuse adjacent said mica pane being substantially narrower than the remainder of the fuse to assure blowing of thefuse in that portion, said narrow portion being of a distinctive color to aid its visibility through mica pane.

In witness of the foregoing I afiix my signature.

THOMAS F. COTE.

1 so a fuse li-nk contacting with one portion only- 

